728 research outputs found
Point sets that minimize -edges, 3-decomposable drawings, and the rectilinear crossing number of
There are two properties shared by all known crossing-minimizing geometric
drawings of , for a multiple of 3. First, the underlying -point set
of these drawings has exactly -edges, for all . Second, all such drawings have the points divided into three
groups of equal size; this last property is captured under the concept of
3-decomposability. In this paper we show that these properties are tightly
related: every -point set with exactly -edges for
all , is 3-decomposable. As an application, we prove that the
rectilinear crossing number of is 9726.Comment: 14 page
Delphi Austria - An Example of Tailoring Foresight to the Needs of a Small Country
The world-wide diffusion and recognition of Technology Foresight suggests that it is of value for quite diverse types of economies and societies. Its merit as an important tool of strategic intelligence for policy-making also in small countries and transition economies depends on a careful tailoring to specific needs. Practice of Foresight is rather diverse also among small countries, but approaches tend to be more selective in scope, have more specific goals, and put greater emphasis on demand aspects than in bigger countries. Austriaâs first systematic Foresight programme (completed in 1998) is an example of an innovative approach adapted to the needs of a small country. This contribution shows how Delphi Austria was tailored to a small economy which had undergone a successful catch-up process and how the Foresight process as well as its results have been utilised.Technology Foresight, Delphi method, small country, Austria, innovation, technology policy, implementation
e-Participation in Austria: Trends and Public Policies
The paper is a first step to assess the status of e-participation within the political system in Austria. It takes a top-down perspective focusing on the policy framework related to citizensÂŽ rights in the digital environment, the role of public participation and public policies on e-participation in Austria. The analysis of the development of e-participation in Austria as well as of social and political trends regarding civic participation in general and its electronic embedding, show a remarkable recent increase of e-participation projects and related initiatives. The paper identifies main institutional actors actively dealing with or promoting e-participation and reviews government initiatives as well as relevant policy documents specifically addressing and relating to e-participation or e-democracy. Finally, it takes a look at the state of the evaluation of e-participation. A major conclusion is that e-participation has become a subject of public policies in Austria; however, the recent upswing of supportive initiatives for public participation and e-participation goes together with ambivalent attitudes among politicians and administration towards e-participation.e-participation, e-democracy, citizensÂŽ rights, institutional actors, public policies, government initiatives, evaluation
Disjoint compatibility graph of non-crossing matchings of points in convex position
Let be a set of labeled points in convex position in the plane.
We consider geometric non-intersecting straight-line perfect matchings of
. Two such matchings, and , are disjoint compatible if they do
not have common edges, and no edge of crosses an edge of . Denote by
the graph whose vertices correspond to such matchings, and two
vertices are adjacent if and only if the corresponding matchings are disjoint
compatible. We show that for each , the connected components of
form exactly three isomorphism classes -- namely, there is a
certain number of isomorphic small components, a certain number of isomorphic
medium components, and one big component. The number and the structure of small
and medium components is determined precisely.Comment: 46 pages, 30 figure
On the Number of Pseudo-Triangulations of Certain Point Sets
We pose a monotonicity conjecture on the number of pseudo-triangulations of
any planar point set, and check it on two prominent families of point sets,
namely the so-called double circle and double chain. The latter has
asymptotically pointed pseudo-triangulations, which lies
significantly above the maximum number of triangulations in a planar point set
known so far.Comment: 31 pages, 11 figures, 4 tables. Not much technical changes with
respect to v1, except some proofs and statements are slightly more precise
and some expositions more clear. This version has been accepted in J. Combin.
Th. A. The increase in number of pages from v1 is mostly due to formatting
the paper with "elsart.cls" for Elsevie
Controlling acquiescence bias in measurement invariance tests
Assessing measurement invariance (MI) is an important cornerstone in establishing equivalence of instruments and comparability of constructs. However, a common concern is that respondent differences in acquiescence response style (ARS) behavior could entail a lack of MI for the measured constructs. This study investigates if and how ARS impacts MI and the level of MI achieved. Data from two representative samples and two popular short Big Five personality scales were analyzed to study hypothesized ARS differences among educational groups. Multiple-group factor analysis and the random intercept method for controlling ARS are used to investigate MI with and without controlling for ARS. Results suggest that, contrary to expectations, controlling for ARS had little impact on conclusions regarding the level of MI of the instruments. Thus, the results suggest that testing MI is not an appropriate means for detecting ARS differences per se. Implications and further research areas are discussed
Upper and Lower Bounds on Long Dual-Paths in Line Arrangements
Given a line arrangement with lines, we show that there exists a
path of length in the dual graph of formed by its
faces. This bound is tight up to lower order terms. For the bicolored version,
we describe an example of a line arrangement with blue and red lines
with no alternating path longer than . Further, we show that any line
arrangement with lines has a coloring such that it has an alternating path
of length . Our results also hold for pseudoline
arrangements.Comment: 19 page
Linear transformation distance for bichromatic matchings
Let be a set of points in general position, where is a
set of blue points and a set of red points. A \emph{-matching}
is a plane geometric perfect matching on such that each edge has one red
endpoint and one blue endpoint. Two -matchings are compatible if their
union is also plane.
The \emph{transformation graph of -matchings} contains one node for each
-matching and an edge joining two such nodes if and only if the
corresponding two -matchings are compatible. In SoCG 2013 it has been shown
by Aloupis, Barba, Langerman, and Souvaine that this transformation graph is
always connected, but its diameter remained an open question. In this paper we
provide an alternative proof for the connectivity of the transformation graph
and prove an upper bound of for its diameter, which is asymptotically
tight
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